Participants with orthodontic fixed appliances will be recruited from the university hospital clinics to receive text message reminders of oral hygiene. Four groups of participants will be formulated. Group 1 will be the control group and will not receive text messages. Group 2 will receive messages once a week. Group 3 will receive text message reminders 3 times a week. Group 4 will receive daily reminders. At baseline, after 4 weeks and after 8 weeks, gingival index and plaque index will be measured at each time point and then compared between groups.